Applying antistatic finish on synthetic textiles

ABSTRACT

A process for imparting antistatic effects on a textile comprising yarn of synthetic fibers which are normally susceptible to pickup of static charge. The process comprises wetting the yarn before it is bulked or dyed with a high temperature stable antistatic agent, forming the wet yarn into skeins wet heating the skeins and then dry heating the skeins until they are dried.

United States Patent [191 Luckenbach Nov. 13, 1973 APPLYING ANTISTATIC FINISH ON SYNTHETIC TEXTILES [75] Inventor: Roy L. Luckenbach, Asheboro, N.C.

[73] Assignee: Burlington Industries, Inc.,

Greensboro, N.C.

[22] Filed: Apr. 5, 1971 [21] Appl. No.: 131,556

[52] US. Cl ..l17/l38.8 UA, 117/138.8 F, 117/1388 N,

[51] Int. Cl B44d l/22 [58] Field of Search... 117/1388 F, 138.8 UA, 117/138.8 N, 139.5 A; 57/157 TS, 157 AS,

34 HS, 34 B [56] References Cited UNITED STATES PATENTS 2,109,087 2/1938 Goodings 117/1395 CF 2,438,366 3/1948 Illingworth 117/1198 Primary Examiner William D. Martin Assistant Examiner- Theodore G. Davis Attorney Cushman, Darby & Cushman [57] ABSTRACT A process for imparting antistatic effects on a textile comprising yarn of synthetic fibers which are normally susceptible to pickup of static charge. The process comprises wetting the yarn before it is bulked or dyed with a high temperature stable antistatic agent, forming the wet yarn into skeins wet heating the skeins and then dry heating the skeins until they are dried.

12 Claims, N0 Drawings APPLYING ANTISTATIC FINISH ON SYNTHETIC TEXTILES The present invention is concerned with a process for applying a durable and otherwise effective antistatic finish on synthetic textiles which normally tend to accumulate undesired static charge. The invention is of particular importance in the treatment of acrylic fibers or blends thereof with other fibers, such as nylon, which are subsequently processed into socks or other fabrics or garments where static pickup is a problem. However, it will be recognized that the invention is broadly applicable to any type of synthetic fibers which present a static charge problem, e.g. nylon.

Various types of antistatic agents and methods of applying the same have been proposed. In the case of dyed fabrics made from bulked yarns, which are of particular concern herein, the antistatic agent is usually applied to the fabric either simultaneously with or after dyeing of the fabric. in some cases, the finish may also be applied to the bulked yarn itself but it is difficult to get a finish which is durable and/or otherwise satisfactory in this way using conventional application techniques. On the other hand, applying the antistatic agent to fabric containing bulked yarns raises other complications, e.g. the dyeing time must be substantially increased when the antistatic agent is combined with dyeing of the fabric.

Typical antistatic agents and method of applying the same are described in U.S. Pat. Nos. 3,108,011; 3,264,815 and 3,510,452. Thus, for example, U.S. Pat. No. 3,108,011 describes the treatment of textiles by impregnating the textile with an aqueous solution of the reaction product of (a) water-soluble polyamines containing polyalkylene oxide radicals with (b) compounds containing more than one epoxide and/or halohydrin group, then contacting the treated textile with a basic aqueous solution having a pH greater than 7.5, rinsing and drying. The treatment described in U.S. Pat. No. 3,108,011 gives a useful antistatic effect but there is considerable room for improvement in the results obtained both as to overall effect, durability thereof to washing and convenience of application.

U.S. Pat. No. 3,264,815 describes application of the antistatic agent (e.g. Stanax" which is said to be a modified water-soluble synthetic resin permanent antistatic agent in the form of a viscous liquid with approximately 50 percent solids prepared according to Examples 1 and/or 12 of British Patent No. 880,897) simultaneously with dyeing by including the antistaticagent in the dyebath after which the yarn is bulked. However, this technique usually requires undesirably longer dyeing times as noted above.

The principal object of the present invention is to provide an improved process for imparting an antistatic effect to textiles, particularly those comprising bulked A highly unique aspect of the process is that the yarn is treated in the greige state before it is bulked and dyed. It is highly unexpected that, by the present treatment, subsequent bulking and dyeingdo not undesirably effect the antistatic properties of the processed yarn. Apparently the unique results of the invention are due to the indicated combination of features, e.g. first wetting with antistatic agent, skeining and then wet and dry heating the skeined yarn although the exact manner in which the invention works to give the desired results is not understood.

Any of the conventional types of antistatic agents which are normally applied to synthetic fibers can be used in the present process provided they are high temperature stable, i.e. stable at bulking and dyeing temperatures. One preferred group of such antistatic agents useful herein is described in U.S. Pat. No. 3,264,815 as the reaction products of alphasulfo higher fatty acids having the following linkage:

I won-c00 wherein the sulfur atom is directly attached to the carbon atom alpha to the carboxyl radical. The unsatisfied valences of the above compounds can be ester or amine radicals. Preferably among these compounds are an organic amine salt of an ester of an alphasulfo higher fatty acid, wherein the alcohol moiety of the ester is a mem ber selected from the group consisting of glycols and ethoxylated alcohols and an organic amine salt of an alphasulfo higher fatty acid, wherein the alcohol moiety of said ester is a higher fatty alcohol.

Another preferred group of antistatic agents for use herein is described in U.S. Pat. No. 3,108,01 l and British Patent 880,897, i.e. the reaction product of watersoluble polyamines containing polyalkylene oxide groups attached to the nitrogen atom and having in the molecule more than one reactive hydrogen atom attached to a nitrogen atom and compounds containing more than one member selected from the group consisting of epoxide and halohydrin radicals having a pH of less than 7. Representative of such agents are the reaction products of dipropylene triamine and polyglycol 600-bischlorohydrin ether. The product Stanax," referred to earlier herein as a modified water-soluble synthetic resin permanent antistatic agent in the form of a viscous liquid with approximately 50 percent solids prepared according to Examples 1 and/or 12 of British Patent No. 880,897, or according to Examples I and II of 3,108,011, is particularly preferred for use herein.

The antistatic agents of U.S. Pat. No. 3,510,452 may also be mentioned as specific examples of products which can be used in the practice of the present invention.

While the amount of antistatic agent applied to the yarn can be widely varied, the amount thereof will usually fall in the range of 0.05 to 5 percent active material, preferably 0.25 to 2 percent, based on the weight of the untreated yarn.

The process of the invention is particularly suitable for finishing textile materials made of polyacrylonitrile, nylon or polyester fibers, and their mixtures with each other or any other synthetic or natural fiber. The process is primarily useful for treating single or plied ends of multifilament yarn to be subsequently bulked and dyed in yarn or fabric form. Typically the processed yarn is used in mens hose or other knitted or woven products such as sweaters, leotards, carpeting, etc. where static pickup is normally a problem, particularly products made of acrylic fibers or blends thereof with other fibersv The aqueous formulation, preferably an emulsion of the antistatic agent in water, is conveniently applied to the yarn at ambient temperature. The application may be accomplished by running the yarn through a conventional winder used to transfer the yarn from a twister bobbin to a conev The yarn on the twister bobbin, with yarn twist only therein (e.g. 2-8 turns per inch) and advantageously comprising two or more ends plied together, can be passed through a tray mounted on the winder and containing the antistatic formulation. The wet yarn is then formed into a skein and the skeins are placed on a rack which is put into a standard H & W Conditioner (i.e., a steam box which is commonly used to pre-bulk yarn), for the purpose of prebulking the yarn and for permanently setting the antistatic agent onto the yarn. In a preferred mode of operation, the conditioner is preheated to 205F. for up to l minutes and water is then fed into the conditioner as a spray or mist, same being converted to steam because of the heat in the conditioner. The resultant wet heat (e.g. l85l95F.) is applied to the skeins for about 1 hour after which the moisture addition is discontinued but the heating is continued until the skeins are dry (at, for example, l95-220F. for 5-20 minutes). Temperature and time conditions may be varied for optimum results depending on the nature of the yarn being processed.

After the indicated heat treatment, which prebulks the yarn, the skeins are allowed to cool and then coned for bulking in conventional fashion, e.g. on well known false twisting or other texturing equipment, knitting or otherwise fabricating the yarn into fabric form, dyeing and finishing. These subsequent steps involving the treated yarn may be carried out in a variety of sequences, for example, the treated yarn may be dyed and bulked simultaneously or sequentially as in U.S. Pat. No. 3,264,815. Bulking can also be accomplished in dyeing fabric, knitted or woven, containing yarn processed according to the invention.

The invention is illustrated, but not limited, by the following examples wherein parts and percentages are by weight unless otherwise indicated:

EXAMPLE 1 One part of the antistatic agent Stanax l 166 (the viscous reaction product of (a) dipropylene triamine and (b) polyglycol-bis-chlorohydrin ether prepared according to Example 2, Step A, of U.S. Pat. No. 3,108,011 and Example 12 of British Patent 808,897, with a pH of about 7.4-7.5) was mixed with 6 parts of water (Formulation A).

Another formulation (Formulation B) was prepared using 4 parts water and 1 part Stanax 1166.

A twister bobbin containing greige (undyed and unbulked) plied yarn (2 ends 1/29 3 denier T-42 unbulked Orlon polyacrylonitrile) was then placed on a Model 50 winder to cone. The yarn traversed over an emulsion roll which applied the antistatic formulation at about 1 percent active solids pickup. Two samples were prepared using Formulation A and Formulation B, respectively. Spindle speed, emulsion roll speed and emulsion roll diameter were, respectively, 980 rpm, 6 l e rpm and 3 inches, for processing both samples.

The sample yarns were wound to skeins and prebulked by conditioning at 205F. dry bulb, 195F. wet bulb for about 1 hour, first under hot moist conditions and then under hot dry conditions. The skeins were then wound back to cones. The thus processed yarns were subsequently knit into mens socks in c0nventional fashion and then dyed in the relaxed state, to give final bulking, the latter taking place by virtue of the heat of the dyebath. The resulting products demonstrated outstanding antistatic properties even after repeated launderings.

EXAMPLE 2 The process of Example 1 was repeated but using instead a single end of greige, undyed polyacrylonitrile yarn (H29 3 denier T-42 unbulked Orl0n), rather than a plied yarn, with equivalent results.

The antistatic properties of the products of Examples 1 and 2, were checked in the manner described in U.S. Pat. No. 3,264,815 using a Rothschild Static voltmeter R1020. This was accomplished by applying a standard charge of volts to the test goods. Thereafter the time (half-life) necessary for one-half the charge to be dissipated was measured, a satisfactory half life being 30 seconds or less. It was found that the half life for goods treated according to the invention depended to some extent on the shade and color of the goods involved. However, in all circumstances, the half life for treated goods did not exceed 30 seconds. More particularly, when the treated goods were dyed light shades or whites for 30 minutes, the half life was only 5 seconds.

With medium shades dyed for 1 '75 hours, the half life was about 15 seconds, while for dark shades (e.g., blacks, navy blue and dark olives), which were dyed for 45 hours, the half life was in the range of 20 to 30 seconds. Dyed control fabrics, dyed and otherwise processed exactly as the fabrics of the invention but omitting the antistatic treatment, gave much higher half lives, substantially in excess of 30 seconds in each instance.

The resistance of the present antistatic finish to laundering is shown by the fact that the static half life of dyed products, prepared according to Examples 1 and 2 herein, remains essentially the same through 25 home washings at F. using conventional home laundering equipment and Tide XK detergent.

The present treatment also improves other properties of the textiles involved. For example, moisture absorbency appears to be substantially enhanced. Additionally, clry-ability is increased by about 50 percent and soil and grease release are significantly improved. Examination of the treated product indicates that the antistatic agent, particularly in the case of the Stanax" type antistats, is cured on the yarn surface so that there is little or no penetration into the fibers. This may be one of the reasons for the improved properties obtainable with the present process although, as noted earlier, the manner in which the treatment herein functions to give the desired results is not understood.

It will be recognized that various modifications may be made in the invention as described above. Hence the scope of the invention is defined in the following claims wherein:

I claim:

l. A process for imparting anti-static effects on a textile comprising yarn of man-made synthetic fibers which are normally susceptible to pickup of static charge, said process comprising wetting said yarn before it is bulked and dyed with a high temperature stable antistatic agent, forming the wet yarn into skeins, then subjecting the skeins to wet heat at 185 205 F. followed by dry heat at 195 220 F. until said skeins are dried and then dyeing and bulking the yarn to give a bulked, dyed yarn which has durable antistatic properties, the antistatic agent being the reaction product of (l) a water-soluble polyamine containing polyalkylene oxide groups attached to the nitrogen atom and having in the molecule more than one reactive hydrogen atom attached to a nitrogen atom and (2) a compound containing more than one radical from the group consisting of epoxide and halohydrin radicals.

2. The process of claim 1 wherein the yarn is made into a fabric after drying but before it is dyed and bulked.

3. The process of claim 1 wherein the yarn is wetted in the greige state and the skeins are dry heated until the antistatic agent is cured.

4. The process of claim 1 wherein the yarn is an acrylic yarn.

5. The process of claim 1 wherein the yarn is wet with said agent by continuously drawing the yarn from a twister bobbin into contact with a kiss roll which applies said agent. 7

6. The process of claim 1 wherein the reaction product is that obtained by reacting dipropylene triamine and polyglycol-bischlorohydrin ether.

7. The process of claim 4 wherein the acrylic is polyacrylonitrile.

8. The process of claim 4 wherein the yarn comprises a single end or two plied ends.

9. The process of claim 4 wherein the yarn comprises an acrylic component and another synthetic fibrous component.

10. The process of claim 5 wherein the wet yarn is formed into skeins, wet heated at l95-205F. and then dry heated at essentially the same temperature until dry.

11. The process for imparting antistatic effects on a textile comprising yarn of man-made synthetic fibers which are normally susceptible to pickup of static charge, said process comprising wetting said yarn before it is bulked and dyed with a high temperature stable antistatic agent, forming the wet yarn into skeins, then subjecting the skeins to wet heating at l85220 F. and then dry heating at 185-220F. until the skeins are dried and thereafter dyeing and bulking the yarn to give a bulked, dyed yarn which has durable antistatic properties, the antistatic agent being the reaction prod uct of l a water-soluble polyamine containing polyalkylene oxide groups attached to the nitrogen atom and having in the molecule more than onqreactive hydrogen atom attached to a nitrogen atom and (2) a compound containing more than one radical from the group consisting of epoxide and halohydrin radicals.

12. The product obtained by the process of claim 1. 

2. The process of claim 1 wherein the yarn is made into a fabric after drying but before it is dyed and bulked.
 3. The process of claim 1 wherein the yarn is wetted in the greige state and the skeins are dry heated until the antistatic agent is cured.
 4. The process of claim 1 wherein the yarn is an acrylic yarn.
 5. The process of claim 1 wherein the yarn is wet with said agent by continuously drawing the yarn from a twister bobbin into contact with a kiss roll which applies said agent.
 6. The process of claim 1 wherein the reaction product is that obtained by reacting dipropylene triamine and polyglycol-bischlorohydrin ether.
 7. The process of claim 4 wherein the acrylic is polyacrylonitrile.
 8. The process of claim 4 wherein the yarn comprises a single end or two plied ends.
 9. The process of claim 4 wherein the yarn comprises an acrylic component and another synthetic fibrous component.
 10. The process of claim 5 wherein the wet yarn is formed into skeins, wet heated at 195*-205*F. and then dry heated at essentially the same temperature until dry.
 11. The process for imparting antistatic effects on a textile comprising yarn of man-made synthetic fibers which are normally susceptible to pickup of static charge, said process comprising wetting said yarn before it is bulked and dyed with a high temperature stable antistatic agent, forming the wet yarn into skeins, then subjecting the skeins to wet heating at 185*-220* F. and then dry heating at 185*-220*F. until the skeins are dried and thereafter dyeing and bulking the yarn to give a bulked, dyed yarn which has durable antistatic properties, the antistatic agent being the reaction product of (1) a water-soluble polyamine containing polyalkylene oxide groups attached to the nitrogen atom and having in the molecule more than one reactive hydrogen atom attached to a nitrogen atom and (2) a compound containing more than one radical from the group consisting of epoxide and halohydrin radicals.
 12. The product obtained by the process of claim
 1. 